Particularly in densely populated areas the infrastructure of gas and water pipes, waste pipes and electric cables and the like is becoming increasingly more complex. Public utilities have charted these mains networks during the last decades or centuries, wherein new networks are included in these maps. It has been found in practice that the data that can be derived from these maps is frequently inaccurate or incomplete, also on account of changes caused in part by building development etc.
In many areas projects have been started to re-map the topography of the network of pipes and cables, to store this in a memory and re-chart the mains networks on a new map from network reference points on the old map. Many old topographical maps were produced in each case according to different land surveying principles and often do not link up to each other. The contents of a new map measured in accordance with a determined principle can therefore be (slightly) shifted or distorted relative to a corresponding old map.
The present invention has for its object to shorten and facilitate the above stated lengthy and labor-intensive operations.
To this end the invention provides a method for charting onto a newly produced map mains networks from an old, existing map, comprising the following steps:
storing in a first memory part the measured data for a new map;
storing in a second memory part the data of the old map including the data relating to the mains networks included therein;
reading from the aforesaid memory parts the new and the old map and displaying the same on a display means;
moving reference points of the old map until these coincide with corresponding reference points of the new map; and
interpolating the network reference points moved with the reference points of the old map so that the network data is included in the new map.
Thus avoided according to the present invention is the need to compare old maps and new maps by a draftsman who is also required to draw the new mains networks therein. Since ultimately a new drawing must be available in digital form in a memory, the map drawn in by hand would then have to be entered into the memory again using a so-called digitalizing table.
For example, the process of re-mapping the province of North Brabant in the Netherlands is of a magnitude which would require more than 100 man years. With the method proposed according to the invention, a time saving of 10-40% can be achieved.